Kabushiki Kaisha Toshiba

Kazushi Tanimoto

Takashi Hikosaka

Shigeru Hoshina

Hiroaki Yoda

Yoichiro Tanaka

Yuji Sakai

Tetsuo Inoue

Tsutomu Tanaka

Yasuo Ohtsubo

Masashi Sahashi

Yuichi Ohsawa

Yutaka Okamoto

Junichi Akiyama

Jun Ito

Yoshiaki Sonobe

Takeo Sakakubo

Hiroshi Ohashi

Hiromi Sakata

Takehito Yamada

Makoto Imamura

Katsuyoshi Kitagawa

Keiko Higashi

Takao Muraoka

Yoshinao Takada

In a disk drive which executes data read operation or data write operation from or into a disk, its CPU determines whether or not the temperature environment of the disk drive is in the high temperature condition exceeding a specified value according to a temperature detection value from a temperature sensor. Under high temperature environment, the CPU aborts re-assignment processing including write operation mode other than ordinary write operation.

Method and apparatus write control in a disk drive

In a magnetic head, at least its upper insulating layer is formed of a resin having a glass transition temperature of 70&deg; C. to 100&deg; C., a porous material, or polyimide, or the ABS is polished at a high temperature, so when the temperature increases, a deformation, which can reduce a decrease in floating height, an increase in the danger of crash, and an increase TA on the part of a magnetic disk apparatus, does not occur on the ABS side.

Magnetic head and magnetic disk apparatus using the same

A magnetic head has a recording/reproducing element which is embedded in an insulation layer made of an AlO.sub.x thin film and a leading end of which is positioned at a medium opposed face. A high-hardness coating layer or a high-thermal conductivity coating layer made of diamond-like carbon or the like is disposed on a peripheral region of the medium opposed face, excluding the leading end of the recording/reproducing element and a region in the neighborhood thereof. Even in the case where the magnetic head is applied to a magnetic disk apparatus of contact recording/reproducing system, it is possible to greatly restrain wear of the leading end of the recording/reproducing element and the region in the neighborhood thereof. Further, the heat dissipation characteristic of the leading end of the recording/reproducing element can be improved greatly. The dishing of the leading end of the recording/reproducing element can be reduced to a great extent by so etching the peripheral region of the medium opposed face that the leading end of the recording/reproducing element is projected; forming the high-hardness coating layer on an etched region; and processing the projected region by wear in a final process.

Magnetic head and method of manufacturing magnetic head

A magnetic disk for writing and reading information by a contact reading method comprises a plurality of asperities upon the surface of the disk. For extending the life of the disk by reducing wear, the plurality of asperities are fabricated such that the average radius of curvature of the plurality of asperities is greater than one thousand times the maximum height of the plurality of asperities on the surface. This ratio between the radius of curvature of the asperities and the surface relief of the asperities ensures a smooth surface and an extended wear life for the magnetic disk.

Surface Characteristics of a Magnetic disk and a magnetic disk apparatus

A magnetic disk drive for carrying out reading/writing of information to/from a magnetic disk having a plurality of tracks including an innermost circumference track and an outermost circumference track. The disk drive includes a rotary actuator and a magnetic head mounted on a magnetic head slider which has separate writing and reading elements. The elements have a magnetic gap for reading and writing the information on a magnetic disk. A rotary actuator arm has one end connected to a rotary actuator and the other end connected to the magnetic head slider. The head slider has an inflow end and an outflow end for the fluid flow generated by the rotation of the disk and at least one bearing which generates a dynamic pressure by the fluid flow. The head is provided close to the outflow. A skew angle created between the magnetic gap length direction and the rotating direction of the disk is substantially constant between the innermost and the outermost tracks. The bearing is arranged at a given angle with respect to the rotating direction so that the outflow end is located on the outer circumferential side of the magnetic disk from the inflow end.

Magnetic disk drive having a constant skew angle

In the read-write apparatus of the present invention, concentrated sliding of the read-write head in a specific area on the recording media is reduced. The recording media is rotationally set and the read-write head contacts the recording media to read and write information on the recording media. While the read-write head is accessing (read/write) the information on the recording media, a slide count calculation section calculates a slide count of the read-write head by monitoring the servo information of the recording media. The memory section stores the slide count calculated by the slide count calculation section by unit of access area. The relocation section suitably relocates the information recorded on the recording media in accordance with the slide count by unit of the access area.

Disk wear prevention by relocating data in response to a head slide count

A hard disk drive includes a magnetic disk used as a magnetic recording medium, and a magnetic head for applying magnetic fields to the disk to record data and for detecting magnetic fields from the disk to reproduce data. During recording and reproducing, the head is moved relative to the disk so as to define a track, which is a series of a number of recording bits, on the disk. At this time, the head is brought into contact with the disk, with a head contact width in the track width direction. The disk has a surface texture which presents a single peak amplitude value falling in a range of being equal to or more than 0.5 nm, and equal to or less than the recording bit length, when the surface texture is factorized into frequency compositions by means of Fourier transform. A wave length for providing the peak amplitude value falls in a range of being ten times the recording bit length or more, and equal to or less than the head contact width.

Hard disk drive

According to the present invention, there is provided a magnetic disk memory system. An embodiment of this system comprises a magnetic disk of a perpendicular recording type, including a soft magnetic backing layer and a magnetic recording layer of a perpendicular magnetic anisotropy formed on the backing layer, and a magnetic head for writing or reading of data with respect to the magnetic disk, wherein the magnetic head comprises (a) a pair of main magnetic poles each of which made of a material having a high magnetic permeability, one end of the each pole being located so as to face the magnetic disk surface, (b) a non-magnetic interlayer provided between two main magnetic poles of the pair, (c) a recording coil disposed so as to generate a magnetic flux passing through the magnetic disk via the main magnetic poles, and (d) an MR element provided via an insulation layer on the other ends of the pair of main magnetic poles, one MR element having a film surface parallel to end surfaces of the other ends of the main magnetic poles, and being magnetically coupled with the pair of main magnetic poles.

Magnetic disk memory system

A magnetic or optical disk apparatus having a flexible disk rotated at high speed and head sliders for reading and writing information on the disk, floating from both sides of the disk. The disk apparatus is also provided with straightening plates for keeping air flow in the radial direction of the disk as a laminar flow to surely prevent the disk from being vibrated at the time when the disk is rotated at high speed. As the result, positions of the head sliders relative to the disk can be surely and accurately maintained to provide heads with excellent recording and reproducing characteristics. Mass storage and high speed access can be thus achieved without damaging the flexible disk and the disk apparatus can be smaller-sized with lighter weight and lower cost.

Flexible information storing disk apparatus having laminar air flow

A magnetic disk storage device has a magnetic disk with a storing/reproduction region formed thereon and a head slider facing the disk surface with a plurality of parallel projections to generate an air bearing. Magnetic heads each having a head gap are provided in the projections and have an interval between head gaps of at least 1/N of the width of the whole storing/reproduction region of the disk where N is the number of heads. The device makes it feasible to increase the number of heads per disk and to shorten the seek distance without increasing the weight of the head actuator.

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Tokyo, Japan

Kazushi Tanimoto